title: Anxiety disorders are independently associated with suicide ideation and attempts: propensity score matching in two epidemiological samples.
abstract: BACKGROUND
  Research suggests that suicidal behavior in individuals with anxiety disorders is attributable to co-occurring risk factors, such as depression. We argue that these conclusions are founded primarily in statistical adjustments that may obscure independent associations. We explored independent associations between specific anxiety disorders and suicide attempts and ideation by means of propensity score matching, a process that simulates a case-control study by creating matched groups that differ in group status (e.g., diagnosis of a specific anxiety disorder) but that are statistically equivalent on observed covariates.
  
  
  METHODS
  We made use of the National Comorbidity Survey Replication (NCS-R) and the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC), which include a total of 43,935 adults. Diagnoses included agoraphobia without panic disorder, generalized anxiety disorder, panic disorder with or without agoraphobia, posttraumatic stress disorder, social anxiety disorder, and specific phobia.
  
  
  RESULTS
  Each anxiety disorder was (95% confidence intervals) associated with increased odds of lifetime suicide attempts (odds ratios 3.57-6.64 [NCS-R], 3.03-7.00 [NESARC]) and suicidal ideation (odds ratios 2.62-4.87 [NCS-R], 3.34-10.57 [NESARC]). Odds ratios for each disorder remained statistically significant after matching on diagnostic status of dysthymia, major depressive disorder, alcohol abuse/dependence, substance abuse/dependence, bipolar disorder I, bipolar disorder II, all other anxiety disorders, and on sociodemographic variables.
  
  
  CONCLUSIONS
  This is the first report to present evidence that each anxiety disorder is associated with suicide ideation and suicide attempts beyond the effects of co-occurring mental disorders. These findings warrant consideration in assessment, intervention, and related policies.
authors.affiliation: Department of Psychology, University of Regina, Regina, Canada.
authors.forename: Michel A
authors.initials: MA
authors.lastname: Thibodeau
authors.forename: Patrick G
authors.initials: PG
authors.lastname: Welch
authors.forename: Jitender
authors.initials: J
authors.lastname: Sareen
authors.forename: Gordon J G
authors.initials: GJ
authors.lastname: Asmundson
mesh_terms: D001008:Anxiety Disorders / Q000453:epidemiology* / Q000523:psychology; D015897:Comorbidity; D003866:Depressive Disorder / Q000453:epidemiology* / Q000523:psychology; D006306:Health Surveys; D016017:Odds Ratio; D057216:Propensity Score; D012044:Regression Analysis; D019966:Substance-Related Disorders / Q000453:epidemiology* / Q000523:psychology; D059020:Suicidal Ideation; D013406:Suicide, Attempted
keywords: GAD/generalized anxiety disorder; PTSD/posttraumatic stress disorder; SAD/social anxiety disorder/social phobia; agoraphobia; anxiety/anxiety disorders; epidemiology; panic attacks/agoraphobia; phobia/phobic disorders; suicide/self harm